Microneedle patch applicator

ABSTRACT

A method and apparatus for application of a microneedle patch to a skin surface of a patient includes use of an applicator. The applicator includes a housing, a slidably disposed applicator plate, and a compression spring. The applicator plate is moveable between a retracted position and a deployed position, and has an engaging surface suitable for mashing up against a microneedle patch and pressing it against a skin surface. A docking system transfers the microneedle patch from a support to the applicator without requiring a user to handle the microneedle patch directly. Once mounted in the applicator, the microneedle patch is deployed against a skin surface of a patient for delivery of a desired agent via a microneedle array contained on the patch.

RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 13/332,065, filed Dec. 20, 2011, which claims priority to, andthe benefit of, U.S. Provisional Application No. 61/426,199, filed Dec.22, 2010, for all subject matter common to both applications. Thedisclosures of said applications are hereby incorporated by referenceherein.

FIELD OF THE INVENTION

The present invention relates to a system suitable for protecting amicroneedle patch and applying the microneedle patch to a skin surface,and more particularly to a system enabling storage of a microneedlepatch in a sterile packaging and transfer and deployment of the patch toa skin surface for delivery of an agent.

BACKGROUND

Microneedle patch technology enables drug delivery into the epidermaland/or dermal layers of the skin. The technology is capable ofdelivering drugs of different types, size, structure, or charge.Microneedle patches can be applied to patients regardless of their skincharacteristics. The patches are optimized to penetrate the shallowlayers of the skin, avoiding pain receptors, and to deliver their drugpayloads.

Application of microneedle patches can be difficult. The patches can bevery small and thus challenging for a patient to handle without damagingand/or contaminating the microneedles prior to application to the skin.Furthermore, microneedle patches must be applied to the skin with asufficient impact to ensure that the microneedles penetrate the skin toa required degree for the intended drug delivery to occur. This presentsadditional challenges to patients using the patches, particularly inself-delivery situations.

SUMMARY

There is a need for a microneedle patch applicator system that canreduce or eliminate the potential for damage and/or contamination of themicroneedle patch due to handling by a patient or user, while alsoensuring the application of the microneedle patch to the skin surface iseffected in accordance with the design parameters for skin penetrationand drug delivery, and in a consistently repeatable manner. The presentinvention is directed toward further solutions to address this need, inaddition to having other desirable characteristics.

In accordance with example embodiments of the present invention, amicroneedle patch applicator includes a housing. A slidably disposedapplicator plate, moveable between a retracted position and a deployedposition in a reciprocating manner, includes an engaging surface. Acompression spring can mount in such a way that imparts a spring forceto the applicator plate when the applicator plate is in the retractedposition. A microneedle patch docking mechanism can be configured insuch a way that the docking mechanism captures and holds a microneedlepatch in a position proximal the engaging surface of the applicatorplate while the applicator plate is in the retracted position. A latchmechanism can be included that when latched holds the applicator platein place and when unlatched permits the applicator plate to move. Theapplicator plate can be placed in the retracted position with thedocking mechanism holding the microneedle patch proximal the engagingsurface, and when the latch mechanism is unlatched, the applicator platecan be propelled by the compression spring to the deployed position.

In accordance with aspects of the present invention, a trigger mechanismcan be included, configured in such a way that activation of the triggerunlatches the latch mechanism. The latch mechanism can be in anunlatched position, enabling the applicator plate to be capable ofretraction to the retracted position in response to a force applied tothe microneedle patch applicator. Unlatching of the latch mechanism whenthe applicator plate is in the retracted position can release theapplicator plate enabling movement from the retracted position to thedeployed position with a kinetic energy of between about 0.1 lbf*in andabout 10 lbf*in, and preferably between about 1 lbf*in and about 2lbf*in.

In accordance with further aspects of the present invention, thecompression spring can have a spring constant of between about 0.1lbf/in and about 50 lbf/in, and preferably between about 2.4 and about8.5 lbf/in. The microneedle patch applicator can deploy the microneedlepatch with sufficient force to anchor the microneedle patch to a skinsurface with a plurality of microneedles disposed thereon. Themicroneedle patch applicator can be stored in a sterile packaging priorto use.

In accordance with example embodiments of the present invention, amicroneedle patch support can include a housing having a perimeterdefining an internal area. An elevated hub can be disposed within theinternal area. The microneedle patch support can be sized anddimensioned to support a microneedle patch in such a way that themicroneedle patch rests on the elevated hub, and any needles extendingfrom the microneedle patch do not make contact with the microneedlepatch support.

In accordance with aspects of the present invention, the perimeterdefining the internal area can be substantially circular in shape. Theelevated hub can be disposed at a location that is substantially at acenter point of the internal area. The elevated hub can include asubstantially mesa shape with a hollow center at a substantially flatportion of a top of the elevated hub. The elevated hub can have a hollowcenter.

In accordance with example embodiments of the present invention, amicroneedle patch applicator system includes an applicator having ahousing. A slidably disposed applicator plate, moveable between aretracted position and a deployed position in a reciprocating manner,can have an engaging surface. A compression spring can be mounted insuch a way that imparts a spring force to the applicator plate when theapplicator plate is in the retracted position. A microneedle patchdocking mechanism can be configured in such a way that the dockingmechanism captures and holds a microneedle patch in a position proximalthe engaging surface of the applicator plate while the applicator plateis in the retracted position. A latch mechanism can be provided thatwhen latched holds the applicator plate in place and when unlatchedpermits the applicator plate to move. The microneedle patch can bedisposed on a support. Upon placement of the applicator onto themicroneedle patch and the support, application of force to theapplicator can cause retraction of the applicator plate to the retractedposition and capture of the microneedle patch by the docking mechanism.

In accordance with aspects of the present invention, a trigger mechanismcan be configured in such a way that activation of the trigger unlatchesthe latch mechanism. When the latch mechanism is in an unlatchedposition, the applicator plate can be capable of retraction to theretracted position in response to a force applied to the applicator.Unlatching of the latch mechanism when the applicator plate is in theretracted position can release the applicator plate enabling movementfrom the retracted position to the deployed position with a kineticenergy of between about 0.1 lbf*in and about 10 lbf*in, and preferablybetween about 1 and about 2 lbf*in.

In accordance with aspects of the present invention, the applicator candeploy the microneedle patch with sufficient force to anchor themicroneedle patch to a skin surface with a plurality of microneedlesdisposed thereon. The microneedle patch can include a plurality ofmicroneedles configured for anchoring the microneedle patch to a skinsurface. The microneedle patch can include a plurality of microneedlesconfigured to contain and deliver a bioactive agent upon attaching to askin surface. The microneedle patch can be stored in a sterile packagingprior to use in the applicator. The microneedle patch can be storedtogether with the support in a sterile packaging prior to use of themicroneedle patch in the applicator. The microneedle patch can containone or more bioactive agents disposed thereon. The support can include aperimeter defining an internal area. An elevated hub can be disposed ata location that is substantially at a center point of the internal area.The elevated hub can include a substantially mesa shape with a hollowcenter at a substantially flat portion of a top of the elevated hub. Theelevated hub can have a hollow center.

BRIEF DESCRIPTION OF THE FIGURES

These and other characteristics of the present invention will be morefully understood by reference to the following detailed description inconjunction with the attached drawings, in which:

FIG. 1 is a cross-sectional view of a microneedle patch applicatorsystem, according to one aspect of the present invention;

FIG. 2A is a perspective view of a top side of a microneedle patch,according to one aspect of the present invention;

FIG. 2B is a perspective view of a bottom side of the microneedle patchof FIG. 2A, according to one aspect of the present invention;

FIG. 3 is an exploded view of the microneedle patch assembled on asupport with a sealing cover, according to one aspect of the presentinvention;

FIG. 4A is a cross-sectional view of the microneedle patch applicatorsystem with an applicator plate in a fully retracted position while themicroneedle patch is being loaded, according to one aspect of thepresent invention;

FIG. 4B is a cross-sectional view of the microneedle patch applicatorsystem with the applicator plate in the fully retracted position and themicroneedle patch docked or loaded, according to one aspect of thepresent invention;

FIG. 4C is a cross-sectional view of the microneedle patch applicatorsystem with the applicator plate in a deployed position and themicroneedle patch positioned for transfer to a skin surface, accordingto one aspect of the present invention; and

FIG. 5 is a flowchart illustrating a method of loading the microneedlepatch applicator with a microneedle patch and deploying the patch on theskin of a patient, according to one aspect of the present invention.

DETAILED DESCRIPTION

An illustrative embodiment of the present invention relates to amicroneedle patch applicator system. The system includes an applicator.The applicator includes a housing, a slidably disposed applicator plate,and a compression spring. The applicator plate is moveable (e.g.,slidable) between a retracted position and a deployed position, and hasan engaging surface suitable for mashing up against a microneedle patchand impacting it against a skin surface. The compression spring mountswithin the applicator in such a way that the spring imparts a springforce to the applicator plate when the applicator plate is in theretracted position. The applicator further includes a microneedle patchdocking mechanism configured to capture a microneedle patch, and a latchmechanism that when latched holds the applicator plate in place. Themicroneedle patch applicator system further includes a microneedle patchdisposed on a support. Upon placement of the applicator onto themicroneedle patch and support, application of force to the applicatorcauses retraction of the applicator plate to the retracted position andcapture of the microneedle patch by the docking mechanism. At thisjuncture, the applicator is then placed on a skin surface of a patientand the latch mechanism is unlatched, releasing the spring force to movethe applicator plate and the microneedle patch rapidly against the skinsurface. Upon impact of the applicator plate and the microneedle patchagainst the skin surface, microneedles of the microneedle patch aredriven into the skin surface, anchoring the microneedle patch to theskin surface and initiating the agent delivery. The compression springmay continue to impart a spring force against the applicator plate whilein the deployed position to hold the microneedle patch against the skinsurface.

FIGS. 1 through 5, wherein like parts are designated by like referencenumerals throughout, illustrate an example embodiment of a microneedlepatch applicator system according to the present invention. Although thepresent invention will be described with reference to the exampleembodiment illustrated in the figures, it should be understood that manyalternative forms can embody the present invention. One of skill in theart will additionally appreciate different ways to alter the parametersof the embodiment disclosed, such as the size, shape, or type ofelements or materials, in a manner still in keeping with the spirit andscope of the present invention.

Turning now to FIG. 1, a microneedle patch applicator system 10 isprovided in accordance with one example embodiment of the presentinvention. The system 10 generally includes an applicator 12 and amicroneedle patch support 14. The applicator 12 includes a housing 16.The housing 16 provides the structure that supports the componentsrequired for the applicator 12. The housing 16 can form an internalchamber 22 in accordance with some embodiments of the present invention.However, an internal chamber 22 is not necessarily required. Onefunction of the internal chamber 22 can be to serve as a guide for themoving components of the applicator 12, as would be understood by one ofskill in the art given the present description.

The housing 16 can be formed of a number of different materials,including but not limited to metal, rubber, wood, plastic, composite,synthetic or natural materials, and the like, such that sufficientstructural support is provided for the intended use of the applicator12.

Furthermore, the housing 16 may include a splaying mechanism or feature(not shown) capable of causing the skin of a patient to stretch when theapplicator 12 is pressed against the skin, making the skin morereceptive of the microneedle patch 38 as delivered by the system 10 ofthe preset invention. One of skill in the art will appreciate how toimplement such a feature.

A slidably disposed applicator plate 18 can be provided, able to move ina reciprocating manner relative to the housing 16. The applicator plate18 includes an engaging surface 20, and can take a number of differentstructural forms. The engaging surface 20 is utilized to engage amicroneedle patch as described herein. As shown, the engaging surface 20is a substantially solid planar surface. However, there is norequirement that the engaging surface 20 have this example structure.The microneedle patch 38 as described later herein has one or moreneedles extending from its surface. The engaging surface 20 need onlyexist in locations so as to be able to mash up against the back of eachmicroneedle to drive it into the patient's skin as described laterherein. The continuous planar surface of the illustrative examplereduces the likelihood that a misaligned microneedle patch would notreceive the appropriate force at the appropriate location to drive themicroneedle as required, but such a continuous planar surface is merelya preferred embodiment, as would be understood by those of skill in theart.

The applicator plate 18, as shown, takes the form of a plunger, capableof sliding movement in a reciprocating manner within the internalchamber 22 of the housing 16. In the illustrative embodiment, the wallsof the internal chamber 22 serve to guide the applicator plate 18 in itsreciprocating movement within the housing 16.

The applicator plate 18 can be formed of a number of differentmaterials, including but not limited to metal, rubber, wood, plastic,composite, synthetic or natural materials, and the like, such that theapplicator plate 18 can operate as intended and described herein.

The slidably disposed applicator plate 18 is moveable between aretracted position and a deployed position. As shown in FIG. 1, theapplicator plate 18 is in a deployed position, demonstrated by theapplicator plate 18 being located at a bottom perimeter edge of thehousing 16, such that the applicator plate 18 can make contact with askin surface, or other surface, if the applicator 12 were placed upagainst such a surface. FIG. 4B shows the applicator plate 18 in a fullyretracted position, as will be described later herein. In accordancewith one example embodiment of the present invention, the applicatorplate 18 can extend slightly beyond the perimeter edge of the housing16, such that contact with a skin surface of a patient is not hinderedby concomitant contact with the perimeter edge of the housing 16.

A compression spring 24 is disposed in the applicator 12, mounted insuch a way so as to impart a spring force to the applicator plate 18when the applicator plate 18 is in the retracted position, as describedherein. One of skill in the art will appreciate that there are numerousways of imparting a mechanical spring force to an object. In the presentillustrative device, the function of the compression spring 24 is togenerate a spring force sufficient to propel the applicator plate 18from a retracted position (as shown in FIG. 4B) to a deployed position(as shown in FIG. 1, and FIG. 4C) in a manner such that an impact forcegenerated by the slidably disposed applicator plate 18 impacting a skinsurface at its deployed position is sufficient to drive a microneedlepatch into the skin surface, as described herein. To achieve such aconfiguration, varying types of springs, spring dimensions, springcharacteristics, spring materials, and the like, can be utilized inconjunction with the applicator plate 18 configuration andcharacteristics to arrive at a desired impact force. Furthermore,different mechanical force translators can be utilized to convey thespring force to the applicator plate 18. Still furthermore, other forcegenerating mechanisms, such as levers, and direct application of forceby a user, can be used in conjunction with or as an alternative to thecompression spring 24, so long as the functionality of the presentinvention is maintained. An illustrative example spring suitable for thepresent application is a spring having a spring constant (k) of about4.7 lbf/in. In experimental instances of the present invention it wasfound that springs having a spring constant (k) of 2.4 lbf/in providedan insufficient spring force when utilized with one embodiment of theapplicator 12 of the present invention to sufficiently drive themicroneedle patch into the skin of a patient. This may have been due toan insufficient compression of the spring. It was further found that aspring having a spring constant (k) of 8.8 lbf/in provided excessiveforce, such that the resulting impact on the skin of a patientapproached an uncomfortable response.

One of skill in the art will appreciate that the present invention is byno means limited to using a compression spring 24 having the specificspring constant (k) provided herein. Rather, one of skill in the artwill appreciate that springs having other spring constants (k) may beutilized, so long as they provide a sufficient force with a given springcompression when used with the applicator 12 to drive the microneedlepatch into the skin of a patient without causing unnecessary pain ordiscomfort to the patient. For example, given the results of the examplespring constants (k), one of skill in the art may appreciate that aspring having a spring constant (k) of between about 0.1 and 50 lbf/in,and including a more likely range of between about 2.4 lbf/in and 8.5lbf/in, results in a device having a generally sufficient impact forcewhile not resulting in undue pain or discomfort to the patient. However,these values can change based on various factors specific to intendedapplications (e.g., age of patient, whether the patient is an animal ora human, etc.) and can be optimized accordingly, as would be appreciatedby one of skill in the art. As the spring constant is merely onevariable in determining the overall force generated, one of skill in theart will appreciate that the compression spring 24 working inconjunction with the applicator plate 18 should create a stored kineticenergy of about 0.1 to 10 lbf*in, with a preferred range of about 1-2lbf*in, when in the retracted position, and further should result in anamount of energy dissipated during implementation of the applicator 12from a retracted position to a deployed position being between about 1-2lbf*in.

The applicator 12 can further include a latch mechanism 26 or assemblyconfigured to latch or lock the applicator plate 18 in place, preventingsliding movement when such movement is not desired. The latch mechanism26, in the illustrative embodiment, is formed of a detent 28 able tomove between two positions along a stepped indentation 30 of a triggercolumn 34. As shown in FIG. 1, the detent 28 takes the form of an o-ringthat is positioned in a fully receded step of the stepped indentation30. In this position, the detent 28 does not apply a substantialpressure against an internal wall 32 of a cylindrical aperture thatpasses through the applicator plate 18 and that contains the latchmechanism 26. As such, the applicator plate 18 is able to move in areciprocating manner up into the housing 16 and then return to thedeployed position. This position of the detent 28 as depicted in FIG. 1occurs when the trigger column 34 is fully depressed by a user. FIG. 4Ashows the applicator plate 18 in a fully retracted position, and alsoshows the trigger column 34 in a raised position. A trigger spring 36 isconfigured in such a way that when the trigger column 34 is depressed, aspring force is generated. When the trigger column 34 is released by auser, the spring force of the trigger spring 36 pushes the triggercolumn 34 upward relative to the applicator plate 18. When the triggercolumn 34 is in a raised position, the detent 28 slides along thestepped indentation 30 to a less receded step. This action forces thedetent 28 radially outward, applying substantial pressure or force tothe internal wall 32 of the applicator plate 18 and to the triggercolumn 34. While in this position, the detent 28 generates sufficientfrictional force to prevent the applicator plate 18 from slidingmovement, thus locking the applicator plate 18 into place. As shown inFIG. 4A, the applicator plate 18 is in its fully retracted position. Thespring force generated by the compression spring 24 is insufficient toovercome the frictional force of the latch mechanism 26 as generated bythe detent 28 as positioned in the stepped indentation 30. As such, theapplicator plate 18 is locked in place.

An example microneedle patch 38 suitable for use with the applicatorsystem 10 of the present invention is shown in FIGS. 2A and 2B from atop perspective view and a bottom perspective view, respectively. Themicroneedle patch 38, as shown, includes a substrate 40 configured in agenerally circular (e.g., relatively short cylindrical) shape. Thesubstrate 40 can have any number of shapes, as would be understood bythose of skill in the art, so long as they are compatible with thecorresponding applicator 12. The substrate 40 includes an aperture 42passing therethrough, substantially at a center point of the substrate40. The microneedle patch 38 further includes a microneedle array 44having a plurality of microneedles coupled with the substrate 40. Themicroneedle array 44 can contain an agent therein for delivery to theskin of a patient upon the microneedle array 44 penetrating a skinsurface 50 of a patient. The term “agent” refers to a single agent or acombination of several agents. The agent may be biologically active orbiologically inactive. Sample agents include, without limitation, drugs,vaccines, allergens, antigens, excipients, anti-coagulants, surfactants,radiological dyes or markers, toxins, or any other agent, compound orsubstance suitable for introduction into a biological environment. Asstored, the agent may be, for example, dry (e.g., a film), or in asemi-solid gel. One of skill in the art will appreciate that otheragents not listed herein can be utilized in conjunction with the presentinvention. As such, the present invention is by no means limited tothose agents specifically listed herein.

A docking mechanism 46 is configured to capture a microneedle patch 38,as shown in FIG. 1 (see also, FIGS. 4A-4C). In the illustrativeembodiment of the present invention, the docking mechanism 46 takes theform of an end section of the trigger column 34. The end section of thetrigger column 34 is sized and dimensioned to form an interference fitwith the aperture 42 of the microneedle patch 38. As will be describedbelow, the docking mechanism 46 when placed through the aperture 42 ofthe microneedle patch 38 frictionally couples with the aperture 42, thusdocking or loading the microneedle patch 38 onto the applicator 12. Onefeature of this docking configuration is that the microneedle patch 38is docked with the applicator 12 in a removable manner. That is, with aforce applied to the microneedle patch 38, the microneedle patch 38 willpull away from the docking mechanism 46 of the applicator 12 relativelyeasily. One of skill in the art will appreciate that a number ofalternative docking mechanisms may be utilized to dock or load themicroneedle patch 38 onto the applicator 12, such that the presentinvention is by no means limited to the specific mechanical embodimentdescribed herein. Rather, it is anticipated that other dockingmechanisms may be utilized with the applicator 12 of the presentinvention to provide a removable coupling of the microneedle patch 38with the applicator 12 in a desired manner. All such equivalent dockingmechanisms are anticipated for use with the present invention.

The microneedle patch applicator system 10 further includes amicroneedle patch support 14. The microneedle patch support 14 isessentially a base structure capable of supporting the microneedle patch38 in such a way that the microneedle array 44 is protected frominadvertent contact during storage or handling. In the embodimentillustrated, the microneedle patch support 14 holds the microneedlepatch 38 with the microneedle array 44 on an inside facing surface ofthe microneedle patch 38 (i.e., the surface facing the microneedle patchsupport 14). The microneedle patch 38 rests on an elevated hub 52, orboss, in an internal area 54 formed by a perimeter 56 edge of thesupport 14 (see also FIG. 3). As illustrated, the elevated hub 52 has amesa shape, meaning essentially a substantially flat top with steepsides, not necessarily vertical, though vertical sides can beimplemented. The substantially flat top provides a surface to engagewith the microneedle patch 38 near a center of the patch, and the steepdrop-off of the sides removes the likelihood of any of the supportstructure interfering with the microneedles of the microneedle array 44.This example configuration directs the microneedles of the microneedlearray 44 inward, and suspends the microneedles within the internal area54, such that they are hidden from a user and not exposed to theenvironment outside of the microneedle patch support 14. Such anorientation of the microneedle patch 38 and the microneedle array 44prevents a user from making accidental or unintended contact with themicroneedle array 44. A sealing cover 58 (see FIG. 3) can be placedacross the support 14 from edge to edge of the perimeter 56, and acrossthe microneedle patch 38, such that the sealing cover 58 appliesdownward pressure on the microneedle patch 38, holding it against theelevated hub 52, and internal walls of the support along the perimeter56 prevent the microneedle patch 38 from sliding laterally relative tothe elevated hub 52, thus holding the microneedle patch 38 in place andin a sealed configuration. Likewise, the sealing cover 58 can be appliedwith clearance between the sealing cover 58 and the microneedle patch38, such that the patch is held substantially in place between theelevated hub 52 (e.g., boss), the sealing cover 58 (e.g., lid), and theperimeter 56. The sealing cover 58 can be adhered to the support 14using a chemical adhesive, a heat seal, or the like. Such an arrangementlends itself to the maintenance of a sterile environment within whichthe microneedle patch 38 can be stored until use.

The microneedle patch support 14 further provides sufficient support tohold the microneedle patch 38 in place when the applicator 12 is placedover the microneedle patch support 14 and the support 14 is used toapply a force to the applicator plate 18 and push it into a retractedposition. As such, the support 14 must be able to withstand at least aforce equivalent to the maximum spring force generated by thecompression spring 24 during such a process of retracting the applicatorplate 18. Generally, the microneedle patch support 14 may be made of agenerally rigid material, including but not limited to, wood, plastic,composite, metal, and the like. A preferred implementation is to formthe support 14 of plastic.

In operation, (and looking to FIG. 5) the microneedle patch applicatorsystem 10 of the present invention can be utilized as follows. With themicroneedle patch 38 resting on the microneedle patch support 14, theapplicator 12 is placed over the support 14 (as shown in FIG. 1) (step100). The trigger button 35 is depressed (step 102), unlatching thelatch mechanism 26 and enabling the sliding movement of the applicatorplate 18. The applicator 12 is lowered onto the support 14 until theapplicator plate 18 makes contact with the perimeter 56 of the support14 (step 104). Such action presses the engaging surface 20 of theapplicator plate 18 against the support 14 at the perimeter 56 of thesupport 14.

A downward force applied to the applicator 12 overcomes the spring forceof the compression spring 24 and lowers the applicator housing 16,retracting the applicator plate 18. Continued application of thedownward force retracts the applicator plate 18 into its fully retractedposition, as shown in FIG. 4A. Likewise, when the applicator plate 18 isin its fully retracted position, the docking mechanism 46 engages withthe microneedle patch 38 at the aperture 42, in accordance with theexample illustrative embodiment. As such, when the applicator plate 18is in the fully retracted position, the microneedle patch 38 is dockedwith the applicator 12 (step 106). In addition, once the applicatorplate 18 is in its fully retracted position, the trigger button 35 isreleased and the latch mechanism 26 latches or locks the applicatorplate 18 in position (step 108). This is also illustrated in FIG. 4B.

As shown in FIG. 4B, with the latch mechanism 26 holding the applicatorplate 18 in the retracted position, the applicator 12 can be lifted offthe microneedle patch support 14 (step 110). Because the microneedlepatch 38 is docked to the applicator 12, the microneedle patch 38 pullsoff of the patch support 14 and stays coupled with the applicator 12 atthe docking mechanism 46.

The applicator 12 is then repositioned against a skin surface 50 of apatient (step 112), and the trigger button 35 is depressed to deploy theapplicator plate 18 and the microneedle patch 38 (step 114), as shown inFIG. 4C. More specifically, this action unlatches the latch mechanism26, again allowing sliding movement of the applicator plate 18. With thestored energy of the compression spring 24, the applicator plate 18 isthrust outward (or downward, as illustrated in FIG. 4C) and impacts theskin surface 50 with the microneedle patch 38. The impact force drivesthe microneedle patch 38, and specifically the microneedle array 44,into the skin surface 50 anchoring the microneedle patch 38 to the skinsurface 50 via the adhesive of the microneedle patch 38. If themicroneedle patch 38 contains an agent, delivery of such agent beginsaccording to design. The applicator 12 can then be removed from the skinsurface 50 (step 116), leaving the microneedle patch 38 anchored/adheredto the skin surface 50. The applicator 12 is then available for futureuse, repeating the process as described herein, for the application ofadditional microneedle patches. Accordingly, the applicator 12 of thepresent invention is reusable. In accordance with one exampleimplementation of the present invention, the applicator 12 can be reusedbetween 30 and 50 times, or more. Each instance of use does require anew microneedle patch to be docked in the applicator 12 and thendeployed to the skin surface 50 of a patient.

One of skill in the art will appreciate that with one example intendeduse of the system 10 being to drive the microneedle array 44 into theskin surface 50 of a patient, it can be necessary to ensure themicroneedle patch 38 and the microneedles of the microneedle array 44are sterile. As such, prior to applying the microneedle patch 38 to theskin surface 50, various processes can be utilized to sterilize themicroneedle patch 38 and the microneedle array 44, including but notlimited to heat, light, or chemical sterilization processes, includingbut not limited to heat sterilization, steam sterilization, gammasterilization, e-beam sterilization, Ethylene Oxide (EtO) sterilization,and the like. Furthermore, components of the device can be individuallysterilized and then aseptically assembled. Such sterilization processesare conventional in the art, though their implementation with theparticular components of the present system 10 is not. Furthermore, themicroneedle patch 38 can be sterilized, together with the microneedlepatch support 14, and both components placed and sealed in sterilepackaging for storage, or the components can be separately sterilizedbefore being sealed in packaging for shipment or storage. When it istime for application of a microneedle patch 38 to a skin surface 50 of apatient, the microneedle patch 38 coupled with the support 14 can beremoved from the sterile packaging by a user, without need for the userto directly handle the microneedle patch 38. Rather, the user can handleonly the support 14, thus maintaining the sterility of the microneedlepatch 38 and the microneedle array 44. The microneedle patch 38 is thendocked to the applicator 12 as described herein, and deployed to theskin surface 50 of a patient, all without anything contacting themicroneedles until they impact the skin surface 50.

A package or packages suitable for protecting a drug-loaded microneedlepatch, as well as the applicator 12, can be provided to maintain themicroneedle patch 38 in a sterile condition prior to use. Suitablepackaging protects the microneedle patch 38 from physical/mechanicalharm, as well as environment conditions (e.g., moisture, oxygen, othervolatiles, etc.), and be a sterile barrier (primary package). Examplematerials include plastic based materials, including plastic compositesand plastic films, metalized plastic films, foil based materials, paperbased materials, or synthetic non-woven materials (e.g., flashspunhigh-density polyethylene fibers) optionally with adhesive (e.g.,pressure sensitive adhesive or hot melt adhesive) that in combinationprovide an airtight an air tight sterile barrier. One of skill in theart will appreciate that a number of different conventional medicaldevice packaging materials meeting these requirements are available foruse with the present invention, and therefore further detail of suchpackaging will not be provided herein.

The agent disposed on the microneedle patch has been defined broadlyherein. More specific illustrative examples of such agent include, butare not limited to, therapeutic agents in all the major therapeuticareas including, but not limited to, anti-infectives, such asantibiotics and antiviral agents; analgesics, including fentanyl,sufentanil, remifentanil, buprenorphine and analgesic combinations;anesthetics; anorexics; antiarthritics; antiasthmatic agents such asterbutaline; anticonvulsants; antidepressants; antidiabetic agents;antidiarrheals; antihistamines; anti-inflammatory agents; antimigrainepreparations; antimotion sickness preparations such as scopolamine andondansetron; antinauseants; antineoplastics; antiparkinsonism drugs;antipruritics; antipsychotics; antipyretics; antispasmodics, includinggastrointestinal and urinary; anticholinergics; sympathomimetrics;xanthine derivatives; cardiovascular preparations, including calciumchannel blockers such as nifedipine; beta blockers; beta-agonists suchas dobutamine and ritodrine; antiarrythmics; antihypertensives such asatenolol; ACE inhibitors such as ranitidine; diuretics; vasodilators,including general, coronary, peripheral, and cerebral; central nervoussystem stimulants; cough and cold preparations; decongestants;diagnostics; hormones such as parathyroid hormone; hypnotics;immunosuppressants; muscle relaxants; parasympatholytics;parasympathomimetrics; prostaglandins; proteins; peptides;psychostimulants; sedatives; and tranquilizers. These agents may takethe form of peptides, proteins, carbohydrates (includingmonosaccharides, oligosaccharides, and polysaccharides), nucleoproteins,mucoproteins, lipoproteins, glycoproteins, nucleic acid molecules(including any form of DNA such as cDNA, RNA, or a fragment thereof,oligonucleotides, and genes), nucleotides, nucleosides, lipids,biologically active organic or inorganic molecules, or combinationsthereof.

Further specific examples of agents include, without limitation, growthhormone release hormone (GHRH), growth hormone release factor (GHRF),insulin, insultropin, calcitonin, octreotide, endorphin, TRN, NT-36(chemical name:N-[[(s)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-p-rolinamide),liprecin, pituitary hormones (e.g., HGH, HMG, desmopressin acetate,etc), follicle luteoids, aANF, growth factors such as growth factorreleasing factor (GFRF), bMSH, GH, somatostatin, bradykinin,somatotropin, platelet-derived growth factor releasing factor,asparaginase, bleomycin sulfate, chymopapain, cholecystokinin, chorionicgonadotropin, erythropoietin, epoprostenol (platelet aggregationinhibitor), gluagon, HCG, hirulog, hyaluronidase, interferon alpha,interferon beta, interferon gamma, interleukins, interleukin-10 (IL-10),erythropoietin (EPO), granulocyte macrophage colony stimulating factor(GM-CSF), granulocyte colony stimulating factor (G-CSF), glucagon,leutinizing hormone releasing hormone (LHRH), LHRH analogs (such asgoserelin, leuprolide, buserelin, triptorelin, gonadorelin, andnapfarelin, sexual or reproductive hormones including gonadotropins suchas menotropin (including extracted, recombinant and synthetic forms ofone or both of urofollitropin (FSH) and LH), oxytocin, streptokinase,tissue plasminogen activator, urokinase, vasopressin, deamino [Val4,D-Arg8] arginine vasopressin, desmopressin, corticotropin (ACTH), ACTHanalogs such as ACTH (1-24), ANP, ANP clearance inhibitors, angiotensinII antagonists, antidiuretic hormone agonists, bradykinn antagonists,ceredase, CSI's, calcitonin gene related peptide (CGRP), enkephalins,FAB fragments, IgE peptide suppressors, IGF-1, neurotrophic factors,colony stimulating factors, parathyroid hormone and agonists,parathyroid hormone antagonists, parathyroid hormone (PTH), PTH analogssuch as PTH (1-34), prostaglandin antagonists, pentigetide, protein C,protein S, renin inhibitors, thymosin alpha-1, thrombolytics, TNF,vasopressin antagonists analogs, alpha-1 antitrypsin (recombinant), andTGF-beta.

The agent can be in various forms, including free bases, acids, chargedor uncharged molecules, components of molecular complexes ornonirritating, pharmacologically acceptable salts. Further, simplederivatives of the agent (such as ethers, esters, amides, etc.), whichare easily hydrolyzed at body pH, enzymes, etc., can be employed.

Additional agents may be included. For example, the agent may include aviscosity enhancing agent, such as maleic acid, malic acid, malonicacid, tartaric acid, adipic acid, citraconic acid, fumaric acid,glutaric acid, itaconic acid, meglutol, mesaconic acid, succinic acid,citramalic acid, tartronic acid, citric acid, tricarballylic acid,ethylenediarninetetraacetic acid, aspartic acid, glutamic acid, carbonicacid, sulfuric acid, phosphoric acid, hydrochloric acid, hydrobromicacid, nitric acid, sulfuric acid, benzene sulfonic acid, methanesulfonic acid, glycolic acid, gluconic acid, glucuronic acid, lacticacid, pyruvic acid, tartronic acid, propionic acid, pentanoic acid,carbonic acid, adipic acid, citraconic acid, and levulinic acid.

Additional potential agents include surfactants, such as zwitterionic,amphoteric, cationic, anionic, or nonionic, including, withoutlimitation, sodium lauroamphoacetate, sodium dodecyl sulfate (SDS),cetylpyridinium chloride (CPC), dodecyltrimethyl ammonium chloride(TMAC), benzalkonium, chloride, polysorbates such as Tween 20 and Tween80, other sorbitan derivatives, such as sorbitan laurate, andalkoxylated alcohols, such as laureth-4.

Still other useful agents include polymeric materials or polymers thathave amphiphilic properties, for example and without, cellulosederivatives, such as hydroxyethylcellulose (HEC),hydroxypropylmethylcell--ulose (HPMC), hydroxypropycellulose (HPC),methylcellulose (MC), hydroxyethylmethylcellulose (HEMC), orethylhydrox-ethylcellulose (EHEC), as well as pluronics.

Further agents include biocompatible carriers, which include, withoutlimitation, human albumin, bioengineered human albumin, polyglutamicacid, polyaspartic acid, polyhistidine, pentosan polysulfate, polyaminoacids, sucrose, trehalose, melezitose, raffinose and stachyose.

Agents can further include stabilizing agents, which can comprise,without limitation, a non-reducing sugar, a polysaccharide or a reducingsugar. Suitable non-reducing sugars include, for example, sucrose,trehalose, stachyose, or raffinose. Suitable polysaccharides include,for example, dextran, soluble starch, dextrin, and insulin. Suitablereducing sugars include, for example, monosaccharides such as, forexample, apiose, arabinose, lyxose, ribose, xylose, digitoxose, fucose,quercitol, quinovose, rhamnose, allose, altrose, fructose, galactose,glucose, gulose, hamamelose, idose, mannose, tagatose, and the like; anddisaccharides such as, for example, primeverose, vicianose, rutinose,scillabiose, cellobiose, gentiobiose, lactose, lactulose, maltose,melibiose, sophorose, and turanose, and the like.

Other agents include “pathway patency modulators”, which can comprise,without limitation, osmotic agents 202 (e.g., sodium chloride),zwitterionic compounds (e.g., amino acids), and anti-inflammatoryagents, such as betamethasone 21-phosphate disodium salt, triamcinoloneacetonide 21-disodium phosphate, hydrocortamate hydrochloride,hydrocortisone 21-phosphate disodium salt, methylprednisolone21-phosphate disodium salt, methylprednisolone 21-succinaate sodiumsalt, paramethasone disodium phosphate and prednisolone 21-succinatesodium salt, and anticoagulants, such as citric acid, citrate salts(e.g., sodium citrate), dextrin sulfate sodium, aspirin and EDTA.

Further agents include a solubilising/complexing agent, for example,alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin,glucosyl-alpha-cyclodextrin, maltosyl-alpha-cyclodextrin,glucosyl-beta-cyclodextrin, maltosyl-beta-cyclodextrin, hydroxypropylbeta-cyclodextrin, 2-hydroxypropyl-beta-cyclodextrin,2-hydroxypropyl-gamma-cyclodextrin, hydroxyethyl-beta-cyclodextrin,methyl-beta-cyclodextrin, sulfobutylether-alpha-cyclodextrin,sulfobutylether-beta-cyclodextrin, sulfobutylether7 beta-cyclodextrin,and sulfobutylether-gamma-cyclodextrin.

Additional useful agents include non-aqueous solvents, such as ethanol,isopropanol, methanol, propanol, butanol, propylene glycol,dimethysulfoxide, glycerin, N,N-dimethylformamide and polyethyleneglycol 400.

Numerous modifications and alternative embodiments of the presentinvention will be apparent to those skilled in the art in view of theforegoing description. Accordingly, this description is to be construedas illustrative only and is for the purpose of teaching those skilled inthe art the best mode for carrying out the present invention. Details ofthe structure may vary substantially without departing from the spiritof the present invention, and exclusive use of all modifications thatcome within the scope of the appended claims is reserved. It is intendedthat the present invention be limited only to the extent required by theappended claims and the applicable rules of law.

It is also to be understood that the following claims are to cover allgeneric and specific features of the invention described herein, and allstatements of the scope of the invention which, as a matter of language,might be said to fall therebetween.

What is claimed is:
 1. A microneedle patch applicator, comprising: a housing; a slidably disposed applicator plate, moveable between a retracted position and a deployed position in a reciprocating manner, the applicator plate having an engaging surface and the applicator plate having a cylindrical aperture that passes therethrough, the cylindrical aperture having an internal wall; a spring mounted in such a way that imparts a spring force to the applicator plate when the applicator plate is in the retracted position; a microneedle patch docking mechanism configured in such a way that the docking mechanism captures and holds a microneedle patch in a position proximal the engaging surface of the applicator plate while the applicator plate is in the retracted position; and a latch mechanism that frictionally engages with the internal wall of the cylindrical aperture to hold the applicator plate in place, and when unlatched disengages from the internal wall and permits the applicator plate to move; wherein the applicator plate is placed in the retracted position with the docking mechanism holding the microneedle patch proximal the engaging surface, and when the latch mechanism is unlatched, the applicator plate is propelled by the spring to the deployed position.
 2. The microneedle patch applicator of claim 1, further comprising a trigger mechanism configured in such a way that activation of the trigger unlatches the latch mechanism.
 3. The microneedle patch applicator of claim 1, wherein when the latch mechanism is in an unlatched position, the applicator plate is capable of retraction to the retracted position in response to a force applied to the microneedle patch applicator.
 4. The microneedle patch applicator of claim 1, wherein unlatching of the latch mechanism when the applicator plate is in the retracted position releases the applicator plate enabling movement from the retracted position to the deployed position with a kinetic energy of between about 0.1 lbf*in and about 10 and preferably between about 1 lbf*in and about 2 lbf*in.
 5. The microneedle patch applicator of claim 1, wherein the spring has a spring constant of between about 0.1 lbf/in and about 50 lbf/in, and preferably between about 2.4 and about 8.5 lbf/in.
 6. The microneedle patch applicator of claim 1, wherein the microneedle patch applicator deploys the microneedle patch with sufficient force to anchor the microneedle patch to a skin surface with a plurality of microneedles disposed thereon.
 7. The microneedle patch applicator of claim 1, wherein the microneedle patch applicator is stored in a sterile packaging prior to use.
 8. The microneedle patch applicator of claim 1, wherein the spring comprises a compression spring. 